Explanation:

The Ajay river originates from Batpar from Chakai block of Jamui district in Bihar. It then enters Jharkhand near Devipur (a proposed industrial area of Deoghar) and flows through Jharkhand and enters West Bengal at Simjuri, near Chittaranjan. It first forms the border between Paschim Bardhaman district and Jharkhand and then between Paschim Bardhaman district and Birbhum district, and finally it enters Katwa subdivision of Purba Bardhaman district at Nareng village in Ketugram police station. It then joins the Bhagirathi River at Katwa Town. Total length of the Ajay is 288 kilometres (179 mi), out of which 152 kilometres (94 mi) are in West Bengal. The catchment area of Ajay River is 6,000 square kilometres (2,300 sq mi). The important tributaries of the Ajay are Pathro and Jayanti in Jharkhand, and Tumuni and Kunur in Bardhaman district of West Bengal. The upper reaches of the Ajay pass through hilly regions with laterite soil. It is only from Ausgram in Bardhaman district that the Ajay flows through alluvial plains. The Ajay valley was densely forested with sal, piyasal and palas trees till recent times when mining and other activities led to the clearing of forests. Recently, Government of India (Ministry of Shipping) declared Ajay River as National Waterway 7, under The National Waterways Act, 2016.